The body temperature of fish, amphibians and reptiles is not constant (variable temperature creatures), but is influenced by the temperature of the environment:
When the environment temperature is high, the body temperature is also high.
When the temperature of the environment drops, its body temperature also drops.
Under a certain temperature the activity stops.
The body temperature of the birds and mammals is fixed (constant temperature creatures), and is not affected by the temperature of their environment.
The temperature of mammals (eg human) is 37 ° C and birds - 40 ° C.
When the environment temperature is high, the body temperature is also high.
When the temperature of the environment drops, its body temperature also drops.
Under a certain temperature the activity stops.
The body temperature of the birds and mammals is fixed (constant temperature creatures), and is not affected by the temperature of their environment.
The temperature of mammals (eg human) is 37 ° C and birds - 40 ° C.